Four basic types of voting equipment are used in US elections.

Optical Scan Paper Ballot Systems (including both marksense and digital image scanners), in which voters mark paper ballots that are subsequently tabulated by scanning devices. On most optical scan ballots voters indicate their selections by filling in an oval (on ES&S and Premier/Diebold ballots), completing an arrow (Sequoia ballots), or filling in a box (Hart Intercivic ballots.) Ballots may be either scanned on precinct-based optical scan systems in the polling place (Precinct Count) or collected in a ballot box to be scanned at a central location (Central Count.)

Direct Recording Electronic (DRE) Systems, in which using one of three basic interfaces (pushbutton, touchscreen or dial) voters record their votes directly into computer memory. The voter’s choices are stored in DREs via a memory cartridge, diskette or smart card and added to the choices of all other voters. An alphabetic keyboard is typically provided with the entry device to allow for the possibility of write-in votes, though with older models this is still done manually.

DRE systems can be distinguished generally by the interface through which the voter indicate her selections. The first generation of DREs used a push-button interface, while later systems use a touchscreen interface. The Hart Intercivic eSlate uses a dial interface. Some DREs can be equipped with Voter Verified Paper Audit Trail (VVPAT) printers that allow the voter to confirm their selections on an independent paper record before recording their votes into computer memory. This paper record is preserved and, depending on State election codes, made available in the event of an audit or recount.

Ballot Marking Devices and Systems provide an interface to assist voters with disabilities in marking a paper ballot, which is then scanned or counted manually. Most ballot marking devices provide a touchscreen interface together with audio and other accessibility features similar to those provided with DREs, but rather than recording the vote directly into computer memory, the voter’s selections are indicated through a marking a paper ballot, which is then scanned or counted manually.

Punch Card Voting Systems Punchcard systems employ a card (or cards) and a small clipboard-sized device for recording votes. Voters punch holes in the cards (with a supplied punch device) opposite their candidate or ballot issue choice. After voting, the voter may place the ballot in a ballot box, or the ballot may be fed into a computer vote-tabulating device at the precinct. Two Idaho counties still used Votomatic Punch Card Voting System in the November 2014 election.

Mechanical Lever Voting Machines First introduced in the 1890s, mechanical lever machines were used in many States during the 20th Century. As recently as 1996, mechanical lever machines were used by 20.7% of registered voters in the United States. Since 2010, no mechanical lever voting machines are used in US elections.

Hand Counted Paper Ballots A significant number of jurisdictions manually count paper ballots cast in polling places by hand and even more count absentees and/or provisional ballots by hand. While not a type of “voting equipment”, beyond the pen or pencil used by the voter to mark the ballot, many of the issues of ballot design and voter intent that effect all voting systems are relevant to hand counted paper ballots as well.